Rayner Generating Station (46 MW) - Wharnclife: Mississagi River

On January 1, 2015, the Ontario Power Authority merged with the Independent Electricity System Operator to create a new organization that combines the OPA and IESO mandates.

Please note that the information on this page is not current and will not be updated. A new format for contract data will be published soon.

The George W. Rayner Generating Station is a two-unit hydroelectric station located on the Mississagi River. The station was designed by Ontario Hydro and built by Rayner Construction Co. between 1947 and 1950, and has an installed capacity of 46 MW at a head of 65 metres.

Located 86 km downstream of Aubrey Falls, it was the first station built on the Mississagi River. Rayner and Wells share the same headpond (Tunnel Lake), dam and sluiceway, and operate in unison to maximize and optimize capacity and energy. Rayner is used as a peaking facility only. The facility includes a dam and spillway, an intake structure and powerhouse. Rayner is equipped with black start capability, which is critical to the restoration of the Northern Power System.

Rayner has two penstocks, which are erected on the sloping downstream face of the main dam. Both penstocks consist of two headgates with trash racks on the inlet to prevent debris from entering the turbine. Each penstock is 74 metres in length and 3.6 metres in diameter.

Rayner is connected to the existing Hydro One 115kV circuit T1B, which is the same circuit used by Red Rock. Circuit T1B, in turn, connects to the 230kV Algoma TS.

This hydroelectric generating station generates approximately 856 MWh of renewable energy per year.

Location: Wharnclife
River System: Mississagi River
Nameplate Capacity: 46 MW
OPA Contracted Capacity: 46 MW
Operator: Brookfield
Technology: Hydroelectric
Turbines: Two vertical Francis turbines
Originally Built: 1950
Coordinate: Longitude 83°-23' -00" Latitude 46°-26'-00"
OPA Contract Term Commencement Date: December 1, 2009


Brookfield Renewable Energy Group

Project Contacts:

Ontario Power Authority

Media and Public Relations
T. 416-969-6307 or

Brookfield Renewable Energy Group

Zev Korman
Investor Relations and Communications
T. 416-359-1955